Push button snap action switch



Oct. 5, 1937. H. A. DouGLAs PUSH BUTTON SNAP ACTION SWITCH 2 shame-sheet 1 Filed May 3l, 1954 /l/E/v Taf? A ay FRY A. @0l/GLAS agg/MJ M A771. l

Oct. 5, 1937. H. A. DOUGLAS PUSH BYJTTON SNAP ACTION SWITCH v 2 sheets-sheet 2- Filed May 5l, 1934 3 QM n.5?. 0

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Patented Oct. 5, 1937 UNITI-:D STATES vNPATEN'r, OFFICE PUSH BUTTON SNAP-ACTION SWITCH Harry A. Douglas, Bronson, Mich., assgnor to I .Kingston Products Corporation, a. corporation of Indiana Application May 31,

2 Claims.

of this applicants prior copending application,

Serial No. 710,279, filed February 8, 1934, now Patent 2,044,065 dated June 16, 1936.'

It is an object of this invention to provide a positive acting switch of this character which is simple in construction and is adapted for use in domestic or automotive lighting systems.

With these and other objects in view, reference is made to the accompanying sheets of drawings which illustrate a preferred embodiment of this invention. with the understanding that detail changes may be made without departing from the scope thereof.

vIn the drawings:- Figure l is a view in central vertical section of a preferred form of this invention with parts shown in elevation.

Figure 2 is a view similar to Figure 1 taken I at right angles to Figure 1.

Figure 3 is a View in transverse section taken on the line3-3, Figure 1, looking in the direction of the arrows. Figure 4 is a fragmentary view in section taken on the line 4 4, Figure 1, looking in the direc-v tion of the arrows.

Figure 5 is a view in section taken on the line aIrOWS.

Figure 6 is a view similar to Figure 1 showing the position assumed by the parts upon the partial depression of the push button just before the circuit is broken and illustrating some of the parts in section.

Figure 7 is a fragmentary view in section taken on the line 1 1, Figure 6, looking in the direction of the arrows.

Figure 8 is a fragmentary detail view similar to Figure 6 showing the switching mechanism in front elevation and including an additional terminal.

Figure 9 is a fragmentary view in section taken on the line 9-9, Figure 8, looking in the direc- `on of the arrows.

Figure 10 is a fragmentary view in section :aken on the line III-I0, Figure 8, looking in the direction of the arrows. I

In the embodiment of this invention illustrated, it is preferable to mo'unt the switching mechanism in a cylindrical metal casing I having-a perforated end 2 for the passage of the reciprocating push button 3, The end 2 is readily secured to 1934, Serial No. 728,286

a support which may be the escutcheon plate mounting strip of awall switchA or the instrument board of an automotive vehicle, by providing an aperture in the support 4 for the passage of the push button 3 and by countersunk screws 5 threaded into correspondingly threaded apertures' formed in the end 2.

The push 'button 3 and operating mechanism actuated thereby is preferably mounted to reciprocate within a metallic guiding sleeve 6 secured to the plate 2 by extending the body of the sleeve to form tongues 'l adapted to pass through vslotsil provided therefore in theend 2 and then bent outward to engage the exterior of the end -2. The axial perforation 9 of the end 2 guides the push button 3 and the portion of the end 2 about the perforation is preferably depressed so that the exterior of the clamped tongues 'I will be in or below the plane of the end 2, as shown in Figures 1 and 5.

The switching mechanism is preferably mounted Within the casing I upon a carrier disc l0 of insulating material preferably secured to the open end of the casing by extending the wall thereof to form depending tongues Il which are passed through peripheral grooves I2 in the disc and bent inward over the exterior of the disc I0.

'I'he push button actuated operating mechanism includes providing the push button 3 with a cylindrical portion adapted to be reciprocated within the axial perforation 9 of the end 2 of the casingand with a rectangular portion I3 Within the casing I forming a shoulder I4 thereon to engage-the margin of the axial perforation 9 to limit the outward travel of the push button. The' horizontal diagonals of the rectangular portion I3 being greaterV than the inner diameter of the guiding sleeve 6, the sleeve is provided with longitudinal grooves I5 for receiving the corners of the portion I3 and prevent rotation thereof during reciprocation. 'I'he rectangular portion I3 and adjacent cylindrical 4portion of the push button 3 is provided with an axial bore I6 and with a central transverse slot I1 extending upward above the shoulder I4 dividing the rectangular portion into two depending legs I8 equally spaced apart from the axis of the push button.

A reciprocating operator R, preferably 'of insulating material, is mounted in the transverse slot Il of the push button 3 upon a pivot pin I9 extending through both legs I8. The body of the operator R. is tapered above the pivot toward the axis of the bore i6 and is terminated short of the end of the slot I'I. A ball 20 is mounted in the push button bore I6 and is held in engagement spring 2 I.

with the operator R by a coil spring 2| compressed between the ball and the end of the bore. The upper end of the operator R is provided with a cutout 22, cut on the arc of a circle concentric with the center of the ball 20, and this cutout 22 normally receives the ball 20 in continuous contact therewith, whereby the longitudinal axis of the operator R normally is maintained coincident with the axis of the casing I. The portion of the reciprocating operator R below the pivot is tapered similarly to the upper side to form a narrower operating end 23 extending below the guide sleeve 6 to cooperate with the actuator A of the switching mechanism to be hereinafter described. As shown in Figures 1 and 2, the spring pressed ball 20 normally maintains the longitudinal center line of the reciprocating operator R coincident with the axis of the casing I. As shown in Figure 6, upon depressing of the button 3, the tapered portions of the reciprocating operator R allow of its oscillation about its pivot I9 when the operating end 23 is brought into engagement with the oscillating operator O of the switching mechanism, as hereinafter described, and whenever such movement is imparted the arcuate upper end 22 of the reciprocating operator R is thrown oi center from the ball 28 and forces the ball upward against the by the junction of the upper tapered sides with the reentrant arcuate top 22 of the reciprocating operator R is such that the said apices always remain on their respective sidesof the axis of the casing I during oscillation so that whenever the button 3 is released from the depressed position the tension of the spring 2I forces the ball 2l) upon the off center portion of the arcuate top 24 imparting a turning movement to the reciprocating operator R about its pivot I9 to return it to its normal position with the surface of the ball 20 in continuous engagement with the arcuate top surface 24.

The contact making and breaking mechanism is all mounted within the casing I above the carrier plate or disc I0. It is preferable to mount two metallic electrical terminals upon the carrier disc I0. As shown in Figures 1, 2 and 6 the terminals are preferably of the construction disclosed in this applicants prior co-pending application, Serial No. 713,713, led March 2, 1934. One terminal 25 is mounted in the axis of the disc I0 with the other terminal 26 mounted on a diameter thereof. Each terminal is provided with a rectangular body depending from the under side of the carrier disc I0 with a portion thereof received in a similar recess to prevent rotation and each upper end of each terminal is of cylindrical formation passing through said contact carrier with the metal of the upper end expanded to engage the interior surface of said carrier to not only secure the terminals thereto but also to form electrical contacts 21.

The middle terminal 25 is passed through the base 28 of a U-shaped metallic bracket and the expanded end thereof forms an electrical connectiongthereto, as shown in Figures 1, 6 and "I, and at the same time mounts the bracket on the inner surface of the carrier I8.

As shown in Figures 1, 6 and '1, the base 28 is centrally perforated to receive the cylindrical portion of the terminal 25. Opposite sides of the base 28 equidistant from its center are continued upwardly at right angles to the base 28 to form parallel arms 29 of similar conformation. It is preferable to provide each arm with an elongated The relation of the apices 24 formedl central cut out portion 30, and with a circular cut out portion 3l thereabove to receive and mount a pivot pin parallel to the base, as will be hereinafter described. It is also preferable to extend each side of each arm 29 adjacent the base to form angularly disposed feet 32 adapted to engage the inner surface of the carrier I0 to impart rigidity to the bracket, and also to provide outstanding fingers 33 on each side of each arm 29 approximately midway between the base 28 and the axis of the circular openings 3 I.

A metallic current continuing bridge B is mounted between the arms 29 of the bracket 28 for oscillation about an axis cutting the axis of the casing I and parallel to the inner surface of the carrier I0. The current continuing bridge is preferably formed from a flat strip of metal centrally struck up to form oppositely disposed simi lar angular surfaces 34 departing downwardly from its transverse center line terminating in flat feet 35 lying in angular planes adapted to be brought into and out of engagement alternately with the contact 21 upon the terminal 26.

It is preferable to provide the carrier disc I0 on the diameter passing through the center of the Contact 21 of the terminal 26 and at an equal distance from the center with an aperture similar to those for receiving the terminals 25 and 25 and mounting therein a metal stud with its opposite ends upset or riveted to the body of the disc I0 to provide a stop 36 similar to the contact 21 of the terminal 26 and adapted to be engaged by the adjacent foot 35 of the bridge B when the contact with the contact 21 has been broken. The metal on each side of the transverse center line is extended outwardly and the sides of the extensions curved upwardly on the arcs of similar circles having their respective centers lying in the transverse center line of the upper surface coinciding with the meeting edge of the angular surfaces 34 to form trunnions 31 whereby the axis of oscillation of the bridge coincides with the meeting edge of said angular surfaces. Each side of the body of the bridge including a portion of each contact foot 35 and the contiguous angular surface 34 is struck up at right angles to the plane of the feet with each portion adjacent to the axis of oscillation provided with a flat surface departing from the body at a similar obtuse angle to the contiguous angular surface 34 to form similar stops 38, the purpose of which will be hereinafter described.

The trunnions 31 are adapted to be mounted in circular or semi-circular bearings concentric therewith to support the axis of oscillation of the bridge half way between and at right angles to the line through the centers of the contacts 21 on the terminals 25 and 25 and a sufficient distance thereabove so that when the bridge is oscillated about its axis the feet 35 thereon will alternately make and break an electrical connection with the contact 21 of the terminal 26. It is preferable to mount the trunnions 31 upon bearings 39 of insulating material supported upon or formed integral with the carrier I0. It is also preferable to form the carrier I Il of a phenolic condensate product known as bakelite so that the supports for the trunnions 31 of the bridge may be formed integral therewith. As shown in Figures 1, 3 and '1, the bottom 40 of the elongated longitudinal apertures 30 in the arms 29 are enlarged and extended to the top of the base 28. 'Ihe trunnions 31 of the bridge extend through these enlarged openings 40 free of all contact or engagement with the supporting bracket and are journaled in bearings 39 formed in the tops .of the lugs 4| extending upwardly from the carrier disc` elongated longitudinal openings 3|) in the arms 29 may be provided with sides 42 departing from each other as they extend downwardly and continued through the base 28 as shown in Figures 8, 9 and 10, whereby the'lugs 4| may provide bearings 39 for the trunnions 31 of the bridge in line with the thickness of the arms 29.

'Ihe circuit continuing bridge B is caused to loscillate by the cooperation of an'oscillating actuator A in conjunction with an oscillating operator O' adapted to be actuated by the oscillating of the operator R upon the reciprocation of the push button 3.

The actuator A is mounted upon a pivot pin 43 mounted in the apertures 3| in the arms 29 of the supporting bracket and includes two similar metallic actuating plates 44 adapted to receive the pivot pin 43 and depend therefrom in sliding engagement with the respective arms 29 of the supporting bracket and terminating short of the'high point of the current continuing bridge, with a' portion of the opposite longitudinal sides struck up at right'angles to the main bo'dy to form right angular anges 45 extending upward from the bottom leaving oppositely disposed similar outstanding arms 46 extending from the body ofthe plate, the longitudinal edges of the flanges 45 are adapted-to engage the similar edges of the v corresponding flanges on the-respective plates 44.

The actuator plates. 44 are. mounted upon the pivot Apin 43 in similar longitudinally elongated bearings 41 allowing a 'sliding bodily longitudinal movement of the plates about the pin 43. The upper surfaces of the actuator arms 46 lie in the sameplane which passes slightly below the axis of the'plvot pin 43 when the upper end of the vbearing 41 is in contact with the upper surface of the pin 43;

A spring housing 48 inthe form of an inverted U is mounted between .the-plates 44 and embraced by the flanges 45,l the extremities of the s ides of the housing are provided with transverse anges 49 adapted to'pass under the lower extremities of the actuator flanges A45 with the terminations thereofinclined upwardly to engage the outer `sidesof theoppositely disposed actuator anges -on each side of the housing and position the base or top of the housing at a distance below the lower end of the actuator bearing 41.- The housoppositely disposed -similar angular flat surfaces 53 departing downwardly from its transverse cen-v ter-line terminating in upwardly 'extending tangential stopslll withthe opposite sides struck downwardly to form depending perforated earsV |55 adapted to bereceived between the actuator plates 44 and receive the pivot pin 43 and mount the operatorO for oscillation there'about below the meeting edge of the surfaces 53 parallel with and in the same plane-as the axis of the pivot and with the'uppersurfacesofthe actuator arms 46 in contact with the under surfaces ofthe tangen- 7 5 tial stops 54 when the lower end of the bearings 41 of the ,actuator are in engagement with the under side of the pivot pin 43. When the bridge B, actuator A and operator O have been assembled upon the supporting bracket the fingers 33 of the bracket arms 29 are bent toward each other, as shown in Figure 2, to prevent the nose 5| from riding over a stop 38 of the bridge.

Figures 1 and 2 illustrate the normal position of the various parts of the switch when the push button is in extended position, from which it is seen that the pivoted operator-R. carried'by the push button 3 maintains its lower or operating end 23 in the axis of the casing and also above one ofthe angular surfaces 53 of the oscillating operator, the foot- 35 of the current continuing bridge B has engaged the contact 21 of the terminal 28 and is maintained in electrical contact therewith by the tension of the spring 52 holding the nose 5| of the detent 50 in engagement with the stop 38 adjacent the closed contact which spring has bodily moved the actuator 44.to slide over the pivot pin 43 to bring the. lower end of its bearing 41 in resilient engagement with the under side of said pivot pin and the actuator arms 46 have contacted both stops 54 of the oscillating operator.

When the button 3 is depressed, the lower end 23 ,of the pivoted operator R is brought into engagement with the angular surface 53 of the oscillating operator and rides thereover, turning l moves the actuator in the direction of the engagedl stop 38 of the bridge until the upper end of the bearing 41 engages the upper side of the pin 43, placing the detent spring 52 under greater tension than normal. As the button 3 continues downward its movement is transmitted through the pivoted operator R to impart a rotative movement to the actuator about its upper bearing on the pivot 43 causing the detent nose 5| to travel over the upwardly inclined surface 34 of the bridge towards its high point, as shown in Figure 6, holding the vcontact with the terminal 26 closed under a slightly increasing .tension of the spring 52 as the nose approaches the high point of the bridge. During this rotative movement the pivot pin 43 acts as the fulcrum of a bell crank lever with power -being applied upon one arm by the operator R at the point of contact P between the oscillating operator stop 54 and the actuator arm 46. During this movement, the point of contact P moves in the direction of the angular surface 34 of the bridge so that as the line from point P to the engaging point of. the nose 5| approaches a rightangle to the surface 34, the friction of the nose thereagainst vis minimized. The movement of the nose 5I toward the high point of the bridge increases the tension of the spring 52 so that just before the nose reaches the high point, the spring 52 bodily moves the actuator away from the bridge to bring the lower end of its bearing 41 into engagement with bridge, power is applied at the lower end of the snap over the high point of the bridge and toA quickly extend the nose I to engage the stop 35 o n the other end of the bridge and thereby quickly oscillate the bridge to break engagement with the contact of terminal 26 and at the same time make engagement with the stop 36.

From the above, it is seen that as soon as the pivoted operator R has rotated the oscillating operator suiiiciently to shift the actuator from its normal pivot 43 to its eccentric pivot P, the spring 52 automatically completes the oscillation to snap one set of contacts out of engagement and the other setv into engagement without requiring further movement of the operator R.

During the depression or inward travel of the button 3, the movement of the end 23 of the operator R traveling over the inclined surface 53 of the operator O imparts a rotative movement to the operator R about its pivot i9 which in turn causes the ball to compress the spring 2| as shown in Figure 6. Upon release of the button 3 the tension of the spring 2i causes the end 23 of the operator R to ride upward over the inclined surface 53 of the operator R as it is being centered by the action of the pressure of the ball upon the arcuate upper surface 22. As the apex or meeting of the inclined surfaces 53 of the operator O is thrown off center on the side of the end 23, the end 23 will pass'thereover as it is being centered by the action of the spring pressed ball 20, so that the extremity of the end 23 when centered will lie over the inclined surface 53 opposite the one over which it completes its travel and be in a position upon the next depression to operate the switching mechanism in the opposite direction. The shoulder i4 upon the rectangular portion of the push button 3 does not engage the under side of the end 2 until the operator R has been centered. When the casing i is in the position shown in the drawings, the button 3 and operator R may, after the operator has been centered, be moved by its weight to bring the extremity of the end 23 in engagement with the operator O as shown in Figure 1.

This invention also contemplates the application of this switching mechanism to a two circuit system by substituting for the stop 38 an additional terminal 28a similar to the terminal 25 with its expanded end 33a acting as a contact to be engaged by the foot 35 of the bridge B when it has broken the circuit from terminal to terminal 26 and thereby establish an additional circuit from terminal 25 to terminal 28a.

As shown and described the parts of this improved switching mechanism excepting the push button, operator R and carrier disc are all adapted to be formed of metal stampings to be easily and quickly assembled. The operating parts are dependable as the spring 52 for imparting the snap movement is fully protected, and the other parts are so constructed that the switch may be operated thousands of times without any ofthe parts deteriorating or getting out of order.

Certain'features, common to the present application and applicants Patent 2,044,065, June 16, 1936, are claimed in the aforesaid patent.

What I claim is:

1. An electric switch, comprising: a base; a pivot structure, carried by said base and providing a pivot; switch actuating means swingable about said pivot and including an operating surface; operating means mounted for reciprocating movement from a normal position to an operating position and including a push button and an operating member pivoted to said button, and resilient means resiliently normally maintaining said push button and said operating member in predetermined relation; said operating means being so constructed and arranged that when in said normal position said operating member rests on said operating surface; and said operating means and said operating surface being relatively so constructed and arranged that when said operating means is moved toward said operating surface force is applied to said resilient means by movement of said operating member about its pivot to store energy in said resilient means and to cause said switch actuating means to swing about said pivot and so that when said operating means is released said operating means is returned to its normal position and the energy for so `returning it is supplied solely by said stored energy.

2. An electric switch, comprising: a base; a pivot structure, carried by said base and providing a pivot; switch actuating means swingable about said pivot and including operating surfaces disposed on opposite sides of said pivot; operating means mounted for reciprocating movement from a normal position to an operating position and including a push button and an operating member pivoted to said button, and resilient means resiliently normally maintaining said push button and saidoperating member in predetermined relation; said operating means being so constructed and arranged that when in said normal position said operating member rests on one of said operating surfaces; and said operating means and each ofsaid operating surfaces being relatively so constructed and arranged that when said operating means is moved toward the operating surface on which said operating member rests force is applied to said resilient means by movement of said operating member about its pivot to store energy in said resilient means and to cause said switch actuating means to swing about said pivot and so that when said operating means is released said operating means is returned to a normal position in which it rests on the other operating surface and the energy for so returning it is supplied solely by said stored energy.

HARRY A. DOUGLAS. 

